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Asgardarchaeota , commonly referred to as Asgard archaea, is a candidatus phylum-rank archaeal clade that includes the closest archaeal relatives of eukaryotes. Despite their prevalence in the scientific literature, the name Asgardarchaeota lacks nomenclatural validation. Here, we describe a novel high-quality metagenome-assembled genome (MAG), AB3033_2TS, proposed to serve as the nomenclatural type for the species Asgardarchaeum abyssi TS according to the rules of the SeqCode. Based on protein content and compositional features, we infer that A. abyssi AB3033_2TS is an acetogenic chemoheterotroph, possibly a facultative lithoautotroph, and is adapted to a thermophilic lifestyle. Utilizing genomes from Asgard archaea, TACK, and Euryarchaea, we perform phylogenomic reconstructions using the GTDB archaeal marker genes, the current reference set for taxonomic classification. Calibrating relative evolutionary divergence (RED) values for Asgardarchaeota using established Thermoproteota lineages in the GTDB r207 reference tree, we establish a robust classification and propose Asgardarchaeum as the type genus for the family Asgardarchaeaceae (fam. nov)., the order Asgardarchaeales (ord. nov.), the class Asgardarchaeia (class. nov.), and the phylum Asgardarchaeota (phyl. nov.). This effort aims to preserve taxonomic congruence in the scientific literature. [ABSTRACT FROM AUTHOR]

• Nonnative (L2) vowel perception is affected by the phonotactic context. • Co-occurrence restriction and surface level alternation can affect how the same L2 vowel contrast is categorised, identified, and discriminated. • The same vowel contrast can have different perceptual patterns due to native phonological interference. • For L2-learning listeners, vowel perception in unfamiliar contexts is predictable from their linguistic experience, especially their vocabulary size in the target language. The study presented here examines how adult L2 listeners' L1 phonotactics interferes with L2 vowel perception in different consonantal contexts. We examined Mandarin listeners' perception of the English /ei/-/iː/ vowel contrast in three onset consonantal contexts, /p f w/, which represent different phonotactic scenarios with respect to the permissibility of Mandarin phonology. L1 Mandarin listeners (N = 42) completed a series of three tasks: a categorisation task, a vowel identification task, and an AXB discrimination task. The results show that English /ei/-/iː/ are perceived as highly contrastive in the /p/ context because both /pei/ and /piː/ constitute a licit sequence in Mandarin phonology. However, participants experience substantial /ei/-/iː/ category confusion in the /f/ and /w/ contexts, where Mandarin listeners repair perceptually by modifying the vowel quality in illicit (unattested) consonant–vowel sequences, i.e., */fiː/ → /fei/ and */wiː/ → /wei/. Further exploratory analyses indicate that L2 listeners' vowel perception in unfamiliar phonotactic contexts is associated with their target language experience, typically indicated by their L2 vocabulary size. The findings thus suggest that the acquisition of novel phonotactic regularities is tied to increased experience with the L2 lexicon. [ABSTRACT FROM AUTHOR]

The functional role of membrane-bound carbonic anhydrases (CAs) has been of keen interest in the past decade, and in particular, studies have linked CA in red muscle, heart, and eye to enhanced tissue oxygen extraction in bony fishes (teleosts). However, the number of purported membrane-bound CA isoforms in teleosts, combined with the imperfect system of CA isoform nomenclature, present roadblocks for ascribing physiological functions to particular CA isoforms across different teleost lineages. Here we developed an organizational framework for membrane-bound CAs in teleosts, providing the latest phylogenetic analysis of extant CA4 and CA4-like isoforms. Our data confirm that there are three distinct isoforms of CA4 (a, b, and c) that are conserved across major teleost lineages, with the exception of CA4c gene being lost in salmonids. Tissue distribution analyses suggest CA4a functions in oxygen delivery across teleost lineages, while CA4b may be specialized for renal acid-base balance and ion regulation. This work provides an important foundation for researchers to elucidate the functional significance of CA4 isoforms in fishes. [Display omitted] • Phylogeny confirms three distinct isoforms of fish carbonic anhydrase 4 (CA4). • CA4a may be the isoform of interest for enhanced tissue oxygen delivery studies. • In salmonids CA4b may be specialized for renal acid-base balance and ion regulation. • CA4c is lost in salmonids and its physiological role is unclear. [ABSTRACT FROM AUTHOR]